1. Field of the Invention
The present invention relates to a sealant to be used in an ink jet recording head for ejecting ink, and to an ink jet recording head using the sealant.
2. Description of the Related Art
Available as a liquid ejection head for ejecting a liquid is, for example, an ink jet recording system for ejecting ink onto a recording medium to perform recording. An ink jet recording head of the ink jet recording system is constructed as illustrated in, for example, FIGS. 1 to 3. FIG. 1 is a schematic view illustrating a top surface of the ink jet recording head and FIG. 2 is a schematic view illustrating a section of the ink jet recording head taken along the line 2-2 of FIG. 1. In addition, FIG. 3 is a schematic perspective view of the ink jet recording head. In FIGS. 1 and 2, an ejection element substrate includes a substrate 1 and a flow-path-forming member 4 formed on the substrate 1. The flow-path-forming member 4 forms an ejection port 3 for ejecting a liquid such as ink and a liquid flow path 5 communicating with the ejection port 3. In addition, the flow-path-forming member 4 may have a liquid-repellent layer (not shown) on an opening surface side of the ejection port. The substrate 1 includes an energy-generating element 2 for generating energy needed for the ejection on its surface (also referred to as “first surface”), and includes a supply port 6 for supplying the liquid to the liquid flow path 5. The ejection element substrate is bonded onto a device hole 7 of a support member 10 having a communication port 9, which communicates with the supply port 6, by an adhesive 8. In addition, after the ejection element substrate has been placed on the support member 10, the ejection element substrate is electrically connected to an electric wiring substrate 12. The ejection element substrate and the electric wiring substrate 12 are electrically connected to each other by, for example, an electrical connection portion 11 (see FIG. 3). The liquid ejection head includes the ejection element substrate, the electric wiring substrate 12 for transmitting an electrical signal for ejecting the liquid to the ejection element substrate, and a tank portion 15 (see FIG. 3) for storing the liquid. In addition, the electrical connection portion 11 between the ejection element substrate and the electric wiring substrate 12 is protected by an electrical-section-sealing portion 13. In addition, a side surface of the ejection element substrate is protected by a periphery-sealing portion 14, and hence the liquid is prevented from accumulating in a space between the ejection element substrate and the device hole 7 of the support member.
A sealant to be used in the ink jet recording head is placed in such a severe environment that the sealant is brought into contact with inks of respective colors containing alkaline and polar solvents and showing different properties. The sealant is required to continue maintaining adhesion reliability and electrical sealing reliability in such condition.
In view of the foregoing, Japanese Patent Application Laid-Open No. 2002-302536 discloses a sealant containing a resin excellent in ink resistance as a main agent, and containing an additive or a filler.